Sterilization and preservation of spices



Nov. 2, 1943. H. E. ALLEN 2,333,505

STERILIZATION AND PRESERVATION 0F SPIGES Filed Sept. 4, 1941 ,Z.1 g

F .5 F" .6 If @ra Patented Nov. 2, 1943 Hugh E. Allen, Northbrook, 111., assignor of onehalf to Albert G. McCaleb, Evanston, 111.

Application September 4, 1941, Serial No. 409,483

9 Claims.

My invention relates to the sterilization and,

preservation of spices. It contemplates effecting heat sterilization of spices, i. e., either whole or ground spices, in manner and under conditions such that their losses of volatile flavors during heat sterilization, and during subsequent storage and handling, are reduced to negligible minima.

The invention is based upon my discovery that spices, if and when coated with wood smoke tar films, are definitely protected against losses of their delicate flavors, while undergoing sterilization at high temperatures and during subsequent storage and handling.

I prefer to effect the heat sterilization of the spices in the same compartment wherein they are provided with their protecting wood smoke tar films; nevertheless I contemplate that the films may be applied in a suitable smoking compartment and the spices then removed to another comparement wherein they are subjected to an appropriate sterilizing temperature by any suitable heating means.

In practicing my invention I prefer to (a) place whole or ground spices in a suitable smoking compartment, (b) smoke the spices at relatively low temperatures to provide them with their protecting films, maintain a pressure of two to three pounds per square inch in the smoking compartment during the film-forming operation, (d) gently agitate the spices during the film-forming operation, and (e) subject the spices to sterilizing temperatures after the protecting films have been formed thereon.

These and other features, objects and advantages of my invention will more clearly appear from the following description and discussion of an illustrative apparatus wherewith my novel method of spice treatment may be practiced, and wherein, in a preferred form, successive steps of the method may be carried to completion in the same chamber or compartment in which it is initiated.

In the accompanying single sheet of drawings Fig. 1 is a vertical sectional view, taken substantially on a median plane extending from front to back, of an optional apparatus adapted for the practice of my invention;

Fig. 2 is a fragmentary vertical section taken on the plane of the line 22 of Fig. 1;

Fig. 3 is a fragmentary view in perspective of a. portion of 'a reciprocating member and cam wheel, showing these parts as they would appear if separated vertically from a normal position; Fig. 4 is an enlarged front elevational view of a pressure relief valve mechanism;

Fig. 5 is a fragmentary view in side elevation of a door clamp; and

Fig. 6 is a plan view of a notched door clamp element.

Referring to the drawing in detail, a cabinet I0 is of air tight construction and is built to hold a normal working pressure of approximately three pounds.

A door II is illustrated as comprising a plate l2 having its marginal edge folded over a flanged channel reinforcing member l3. A sealing gasket M, which may be of bronze-covered asbestos, is interposed between the door and an angle iron reinforcing frame secured around the margin of the door opening.

A plurality of fasteners such as screw clamps l5 may be provided at suitable intervals around the marginal edge of the door to draw the door into close, sealed position with the cabinet. The clamps l5 each may comprise a bolt l6 pivotally mounted in a bracket l'l secured to the cabinet wall beyond the door opening. A nut I8 is threaded onto each of the bolts l5, and is pro' vided with a pair of divergent bar grips for manipulation.

An arched clamp member I9 is secured to the door in position to register with each of the bolts 18, and is provided with a notch 20 in its outer end to receive the bolt It for clamping'the door in place.

A double element burner 2| is provided for the control of an initial smoke tar coating step and supplementary and subsequent sterilizing step. The burner 2| may comprise a pair of electrical resistance units 22 and 23 mounted on a suitable supporting frame 24. Conductors 25 are connected to the heating units, and, through selec' tive switch means not'shown; to a suitable supply of electricity.

The smaller of the two burner elements 22, is adapted to receive a pan 21 containing a measured quantity of suitable smoke generating material such as hickory wood chips or sawdust. The

quantity of smoke generating material should be 31 and 38 of the bar 34.

ible through the door opening onto the brackets 26, and are preferably formed with wired rolled edges 32. The rolled edges of the trays .are adapted to be inserted between the jaws of spring clips 33, carried by a horizontally reciprocating bar 34 mounted vertically at the rear of the cabinet.

One of the clips, shown in detail in Fig. 3, is mounted to receive and grip the rear rolled edge of each tray when mounted on its supporting brackets. The forward ends of the bracket jaws are beveled outwardly as at 35 to provide cam surfaces to cause a separation of the jaws when the rolled edge of the tray is forced against them. A coil spring 36, held in compression between the jaws rearwardly of their pivotal connection, is of sufiicient strength to grip the tray during a reciprocating movement of the bar 34, but to permit manual withdrawal of the tray upon completion of the processing.

The bar 34 is provided with right angle end portions 31 and 38, which, together with a centrally mounted arm 39, are provided with slotted'openings 40 which receive a vertical shaft 4| to permit limited longitudinal movement of the bar 34. The shaft 4| is driven at its upperend by a geared electric motor 42. The end portions 31 and 38 of the bar 34 are mounted slidably in grooved blocks 43 and 44, respectively, which guide the .bar during reciprocation and prevent it from turning. v

'A cam pin 45 (see Fig. 3) is mounted just rearwardly of the slot 40 in the arm 39, and similar cam pins also are mounted in the end portions A cam 46 is secured to the shaft adjacent each of these members, the earns 46 each being provided with an eccentric cam slot 41 to cause, upon rotation of the shaft 4|, a iore-and-aft reciprocation of the bar 34 and its clip-held trays 36.

A pressure blower 46, such as a Root type blower, may be mounted to discharge as at 49 into the interior of the cabinet. The blower should be capable of rapidly building up the air pressure within the cabinet and maintaining it at approximately three pounds to the square inch.

An electric motor 56 has driving connection with the blower and is connected, through a pressure controlled switch to a suitable source of electricity. The switch is controlled by a pressure sensitive bellows 53 mounted within the cabinet and connected by tubing 54 to the switch. The degree of pressure within the cabinet may be varied by means of an adjusting screw 55 .mounted on the pressure controlled switch.

of about three pounds to the square inch, a pres-- sure operated relief valve 51 is mounted-in a valve opening in the top of the cabinet to discharge into a stack collar 58.

A link 56 connects the valve to an arm 66 which I is pivoted on a bracket 6| secured to the stack collar 56. A coil spring 63 encircles an adjusting screw 64 and is held in compression between the arm 60 and a head 65 on the lower end of the screw 64. The adjusting screw is threaded to an arm of the bracket 6| whereby the spring pressure on the valve 61 can be adjusted, so that the valve will be opened by an internal pressure of about three pounds per square inch.

A latch pin 66 is mounted slidably in an opening in the bracket 6| and is encircled .by a light coil spring 61 normally to hold the pin with its head 68 close to the bracket out of the way of the valve arm 60. The arm 60 extends forwardly beyond the screw 64 to form a handle portion. By pressing down on this handle portion to bring the arm 60 below the pin 66, and then pressing the latch pin into-the dotted line position of Fig. 4, the arm 6| will be latched in such position and the valve 51 will be held open. Downward pressure on the handle portion of the arm 68 to free the pin 66 permits the spring 61 to restore the pin to its normal solid line position of Fig. 4 and again releases the arm 60 for spring-controlled valve-closing movement.

A combined temperature and pressure indicator 69 is provided to permit an operator to check these conditions within the cabinet at various stages of the process.

Heat treatment alone at sterilizing temperatures has not been practicable, since it drives off the more volatile ends of the essential oils of the spices, and hence causes a material loss of their aroma and flavor.

In practicing my invention I spread a quantity of spice to be treated in the bottom of each tray, so as to form a relatively shallow layer of spice covering the bottom of the tray. The trays thus partially filled are inserted in the cabinet on the brackets 29 and are pushed in until their rear rolled edges are gripped by the clips 33. The motor 42 is then energized to cause a, reciprocal agitation of the trays.

The pan 21 is filled with a suitable quantity of chips, depending upon the size of the cabinet,

and the small burner unit is energized. The door II is then closed and drawn down tight by the clamps l5. The valve 51 may remain open during the initial phase of the process, being held in open position by the latch pin 66 as previously described.

The blower 48 may be operated as required during this initial smoke tar coating phase of the process to supply suflicient air for the proper production of smoke during the destructive distillation of the material in the pan 21, and to maintain the temperature within proper limits, which is preferably approximately F. For this purpose suitable speed control apparatus may be provided for the blower drive, or the blower motor may be operated intermittently for short periods as required. At most but a small amount of air, if any, is required during this phase, and the amount is not criticaL.

Each grain or particle of spice thus will be uniformly coated'with a thin covering of a tarry film composed of characteristic minute globlues. The agitation of the spices during this phase assures that. the entire surface 'of each grain of spice will at times be exposed to the direct action of the smoke, which precludes the possibility of uneven coating which might occur if the grains were permitted to remain at rest andin contact with each other.

Upon completing the smoke tar coating stage of the process, the burner 22 may be de-energized, and the larger burner 23 energized; The pressure control valve 51 is released from its raised, inoperative position as above described, and the blower 48 may be operated to build up the pressure within the cabinet. The pressure switch may be adjusted to maintain a required pressure in the cabinet, i. e., from two to three pounds to the square inch, and the valve is adjusted to valve out, air if a maximum pressure of, for instance, three pounds to the square inch is exceeded. The temperature during this sterilizing stage of the process is maintained at about 212 F., or even considerably higher, for a period of approximately two hours. The amount of mold spores and bacteria present in various spices varies within relatively wide limits, and the sterilizing time and temperature may likewise be varied to provide a minimum sterilizing temperature and time. Such data may be determined by testing a sample batch of spice to be treated before and after a treatment under the specific conditions herein set forth, and then modifying the treatment of subsequent batches as indicated by the results of such test.

During this secondary sterilizing stage of the process agitation by means of the shaft 4| and associated mechanism may be continued, but is not essential, and I contemplate withdrawing the trays 30 from the cabinet ID on completion of the smoke tar coating step, and placing them in another cabinet, which may be similar to that illustrated, but Without the necessity of having the smoke coating and agitating features herein provided. With such an arrangement one smoke coating cabinet with its shorter period of operation could supply several heat sterilizing cabinets with resultant economy and greatly increased production.

While I may process whole spices, it is not essential that the spices shall be in the whole or unground state, and the process is adapated for use with spices ground to varying degrees of fineness.

Spices treated by my improved process maintain their initial flavor strengths without the need for subsequent addition of essential oils as is required when spices are sterilized by heat treatment alone. In addition, by reason of the smoke tar deposit acquired during the early part of the process, they may have a rich smoky flavor of value in the cooking, tenderizing and preserving of meat and meat products.

I have found that a very thin smoke tar fllm is sufficient for flavor strength preservation during sterilization and later, although heavier coats may be applied when it is desired that the spices shall introduce much wood smoke flavor into the ultimate food products.

While I have thus described my new process and illustrated a representative apparatus for practicing it, I contemplate that it may be modifled within the ranges defined by the appended claims. and may be practiced with other apparatus than that of the specific embodiment illustrated and described.

I claim:

1. A method of sterilizing and preserving spices which consists in smoking them to deposit protecting films thereon and subjecting the flimprotected spices to a sterilizing temperature.

2. A method of sterilizing and preserving spices which consists in introducing them into a closed compartment, simultaneously smoking and agitating the spices in said compartment to deposit protecting fllms thereon, and then developing a sterilizing temperature in said compartment before removing the spices therefrom.

3. A method of sterilizing and preserving spices which consists in introducing theminto a closed ompartment, simultaneously smoking and agitating the spices in said compartment to deposit protecting fllms thereon, and then developing a sterilizing temperature and pressure greaterthan-atmospheric in said compartment before removing the spices therefrom.

a. A method of treating spices which consists in coating spices with a uniform fllm of wood smoke tar and thereafter exposing the spices to a gaseous atmosphere under increased pressure and simultaneously heating the spices to a sterilizing temperature;

5. A method of treating spices which consists in depositing air-borne wood smoke tar particles on spices in a substantially even unbroken film,

and thereafter increasing the pressure on such spices and simultaneously heating such spices to ing the spices to expose directly the entire outer surface area thereof to such atmosphere, thereafter increasing the temperature of such spices to approximately 212 F. and simultaneously in- .creasing the pressure on said spices two to three pounds per square inch above the initial pressure of such atmosphere.

8. A method of treating spices whichconsists in exposing spices to a smoky atmosphere to cause a deposit thereof of wood smoke tar, of maintaining said spices relatively cool during suchsmoke. tar depositing step, and thereafter simultaneously increasing the temperature of the spices to approximately 212 F. and the pressure of said atmosphere two to three pounds per square inch and maintaining such increased pressure and temperature during a sterilizing period.

9. A method of treating spices which consists in spreading the spices in shallow layers on a surface capable of agitation, surrounding the spices so arranged with a gaseous atmosphere in which are suspended innumerable smoke tar particles, agitating said surface and thereby the spices supported thereon to produce a continual shifting'of the position of the spices relatively to each other to expose all external surface pottions thereof to the smoke tar'particles to produce a substantially even unbroken film-of such tar particles on said spices, thereafter increasing the pressure of said atmosphere on said spices tending to force the tarry deposit inwardly on said spices and, simultaneously with the pressure increase, increasing the temperature of said spices to a sterilizing temperature.

HUGH E. ALIEN. 

